masterThesis
Modelos log-simétricos com fração de cura
Fecha
2018-05-29Registro en:
ROCHA, Joyce Bezerra. Modelos log-simétricos com fração de cura. 2018. 91f. Dissertação (Mestrado em Matemática Aplicada e Estatística) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2018.
Autor
Rocha, Joyce Bezerra
Resumen
Long-term models are of great interest in statistical modeling that involves time-to-event
data in which a fraction of the population is immune to this event. For these models, also
known as cure fraction models, there are in the literature several proposals considering
parametric aproach. We propose and study properties of the long-term model considering
that the distributions of lifetimes of the susceptible individuals belong to the logsymmetric
class of distributions. This class is characterized by continuous, strictly positive
and asymmetric distributions including distributions such as log-t-Student, log-logistic I,
log-logistic II, log-normal-contaminated, log-exponential-power, log-slash, among others.
The log-symmetric class is quite exible to include bimodal distributions and t dataset
with outlying observations. In this model, here called the log-symmetric model with cure
rate, the explanatory variables are included through the parameter associated with the
cure fraction. We evaluate the performance of the proposed model through extensive simulation
studies and consider an application to real data in a study to identify factors
which in uence the immunity of leprosy reactions in patients with leprosy.